MAINE INDOOR AIR QUALITY COUNCIL 

Using Air Purifiers

General Information

A variety of "air purification" products are now sold in hardware, electronics and specialty stores.  Property owners should know that air purifiers are effective for certain applications, as long as they don't expose people to harmful levels of ozone. 

Recommendations for Use of Air Purifiers

Air purifiers can be effective to reduce exposure to cat or dog allergens in a bedroom or other specific area of a home.  Air purifiers can also be effective in reducing unavoidable odors.  Air cleaners are not generally recommended for dust mite reduction, as the breeze generated stirs up more mite allergen than it removes.  High Efficiency Particulate Air (HEPA) filters are preferred.   Air purifiers with HEPA filters will be most effective if the air ducts, doors and windows in the room are closed and if they run 24 hours a day.  Follow the manufacturer's instructions and change the filters regularly, roughly every 3-6 months.   For additional guidance on the types of products available and their effectiveness for air cleaning, see Residential Air Cleaning Devices:  A Summary of Available Information.

Ozone Generators

Property owners considering purchasing an air purifier should carefully research the product being purchased.  Products that use a low-energy charge to deposit particles on charged metal layers may emit ozone into the indoor environment.  This type of product is not recommended.  Ozone is dangerous for asthmatics and causes headaches in many susceptible people.  Ozone has a sweet smell and causes people to think the filter is "cleaning" the air, rather than just emitting a smell into the room.  The U.S. EPA has some excellent information about air purifiers that produce ozone and their effect on health.  See Ozone Generators That Are Sold As Air Cleaners:  An Assessment of Effectiveness and Health Consequences.

Protect Yourself From Adverse Health Effect

Property owners should carefully research an air cleaning device prior to purchase to insure that it will safely accomplish your desired air cleaning task.  Not all products are the same, and there are risks and benefits of each.  After purchase, property owners should strictly adhere to the manufacturer's recommendations for safe use and operation of the product.

Web Links for additional information

U.S. EPA - wide variety of information on indoor environmental pollutants and tips for addressing them:

www.epa.gov/iaq

American Lung Association - lots of information on asthma and general lung health

Residential Air Cleaning Devices:  Types, Effectiveness & Health Impact